Table with stabiliser

ABSTRACT

The invention relates to a table comprising at least three legs and a stabiliser. The stabiliser comprises a rotatable member extending outwardly from a vertical axis of the table. The table may be stabilised by locating the table on the ground such that three legs of said table contact the ground and the stabiliser is not in contact with the ground, and then rotating the rotatable member so as to cause it to come in contact with the ground.

TECHNICAL FIELD

The present invention relates to a stabilisable table.

BACKGROUND OF THE INVENTION

Tables in commercial premises such as restaurants and outdoor cafés often have a problem with stability due to uneven floor or ground surfaces. The most common design of table used in these environments has a central post with four or more legs radiating outwardly in a substantially horizontal direction.

These tables may rock and possibly tip due to the uneven surface of the floor or pavement. The table legs may also be of uneven length because of manufacturing tolerance or general wear and tear, leading to additional instability. To prevent rocking of the table staff and patrons will often insert paper, wood or other material or a wedge (see for example U.S. Pat. No. 5,249,767) under the high leg. This is not ideal as it involves manual handling which is inconvenient and may jeopardise hygiene when handling food. Also, if the table is moved then the wedge may need to be reset.

Solutions have been developed such as US Patent Application 2006/0054065. However, such systems are commonly complicated and prone to damage. Other solutions have been developed, such as U.S. Pat. No. 6,009,815, however this system is a complex hydraulic system which is expensive to produce.

OBJECT OF THE INVENTION

It is the object of the present invention to substantially overcome or at least ameliorate one or more of the above disadvantages.

SUMMARY OF THE INVENTION

In a first aspect of the invention there is provided a table comprising at least three legs and a stabiliser, wherein said stabiliser comprises a rotatable member extending outwardly from a vertical axis of said table.

The following options may be used in conjunction with the first aspect, either individually or in any suitable combination.

The stabiliser may comprise a rotation device. The rotation device may enable diagonal rotation of the rotatable member.

The rotatable member may be rotatable through a horizontal non-zero angle of up to about 60°. In some embodiments the rotatable member is rotatable through a horizontal non-zero angle of greater than about 60°, e.g. up to about 120°.

Rotation of the member through a horizontal angle may be accompanied by vertical movement of a distal end of said member. The vertical movement may be through a non-zero angle of up to about 4°. In some embodiments the vertical movement may be through a non-zero angle of greater than about 4°, e.g. up to about 20°.

The rotatable member may comprise a foot for contacting the ground. The foot may be disposed at or near the distal end of the member. The foot may have a high friction ground-contacting surface. Each of the legs of the table may, independently, have a foot for contacting the ground. The/each foot may have a high friction ground-contacting surface.

The rotation device may comprise a diagonal cam. It may comprise a cam follower. The cam follower may be disposed to fit the diagonal cam so as to follow said cam as the rotatable member is rotated.

The rotation device may comprise a hinge having a non-vertical hinge axis. The hinge axis may be at an angle of greater than about 80° to the horizontal. The hinge axis may be located in a vertical plane which extends radially, or approximately radially, from the table axis. The hinge axis is preferably angled outwardly from its upper end. Alternatively the hinge axis may be located in a circumferential plane, i.e. in a vertical plane which is tangential to a circle whose centre is the table axis. In this case, when viewed from the distal end of the rotatable member towards the table axis, the hinge axis may be tilted sideways, either to the right or to the left.

The table may comprise a return mechanism for returning the rotatable member to a central position. The central position may be one in which the rotatable member is located in a plane which extends radially from the table axis.

The rotatable member may be operable by a foot of an operator.

The table may comprise a locking mechanism for releasably locking the rotatable member in a fixed position.

The legs and the stabiliser may be coupled to a support shaft which supports a tabletop. Alternatively they may be directly coupled to a tabletop so as to support said tabletop.

In a second aspect of the invention there is provided a method for stabilising a table according to the first aspect, said method comprising:

-   -   locating the table on the ground such that three legs of said         table contact the ground and the stabiliser is not in contact         with the ground; and     -   rotating the rotatable member so as to cause said member,         optionally a foot thereof, to come in contact with the ground.

The rotating may be caused by the foot of an operator. The rotating may be through a horizontal angle of less than about 60°. It may be through a horizontal angle of less than about 30° either side of a central position.

The rotatable member may comprise a foot for contacting the ground. In that case, the foot may be disposed at or near the distal end of the member. The step of rotating may cause the foot to come in contact with the ground.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings wherein:

FIG. 1 is a diagram of a table according to the invention: a) showing the rotatable member in a central position, b) showing an expanded view of the hinge, c) showing rotation of the rotatable member, d) showing the rotatable member rotated anticlockwise so as to elevate the member, and e) showing the rotatable member rotated clockwise so as to lower the member;

FIG. 2 is a diagram of a table according to the invention, comprising a cam for rotating the rotatable member: a) showing an expanded view of the cam, b) showing an expanded view of the cam so as to illustrate the underside of the cam, c) viewed along the rotatable member and showing an expanded view of the cam, d) showing the rotatable member rotated anticlockwise so as to elevate the member, and e) showing the rotatable member rotated clockwise so as to lower the member;

FIG. 3 is a diagram of a table according to the invention, showing an expanded view of the hinge: a) isometric view, and b) from the side looking along one of the fixed legs;

FIG. 4 is a diagram of a table according to the invention, in which the hinge allowing rotation of the rotatable member is located on a fixed member; and

FIG. 5 is a diagram of a table according to the invention having a return mechanism: a) isometric view showing an expanded view of the hinge and b) horizontal section through the table and the hinge.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention is directed to a table which may readily be adjusted so as to be stable, i.e. not to rock, even when located on an uneven or non-flat surface. Whereas a table having three legs may be readily located on a surface such that all three legs contact the ground, a three legged table is commonly not very stable. However addition of a fourth leg so as to improve stability provides the possibility that not all four legs will be able to contact the ground simultaneously, particularly if the legs are not all of precisely the same length and/or if the table is located on an uneven surface. Thus the table of the present invention comprises at least three legs, commonly exactly three legs but optionally more than three (e.g. 4, 5 or 6 legs), and a stabiliser.

The stabiliser comprises a rotatable member. The member is rotatable horizontally. In particular it is rotatable horizontally in such a way that horizontal rotation of the member is accompanied by an attendant vertical rotation or movement of thereof. Thus the member may be capable of rotating diagonally. Thus commonly the rotatable member is capable of rotating in a plane which is at an angle to the horizontal, or of rotating so that the distal end of the rotatable member moves in a plane which is at an angle to the horizontal. The angle of the plane may be about 1 to about 45° to the horizontal, or about 1 to 20, 1 to 10, 1 to 5, 2 to 45, 5 to 45, 10 to 45, 20 to 45, 2 to 10, 2 to 5 or 5 to 10°, e.g. about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 35, 40 or 45°. As the member, or the distal end thereof, rotates in this angled plane, there will be a horizontal component of the rotation and a vertical component of the rotation. Commonly the horizontal component of the rotation will be greater than the vertical component, i.e. for a particular rotation the distal end of the member will move further in a horizontal direction than in a vertical direction.

The rotatable member commonly extends in a generally outwardly direction from a vertical axis of said table (referred to here in as the “table axis”). The vertical axis of the table may be an axis from which the legs (particularly the fixed legs) extend. It may for example correspond to the axis of a central vertical post of the table. It may be an axis passing vertically through the geometric centre of the table top (or vertically through its centre of gravity, particularly in the case of a table having an irregular shaped table top). In common embodiments the axis of rotation of the rotatable member is at or near the vertical axis of the table. In this case the rotatable member will extend substantially radially outwards from the vertical axis of the table. In other embodiments, as discussed later in this specification, the stabiliser comprises a fixed member and a rotatable member. In some such cases, the axis about which the rotatable member can rotate may be some distance from the axis of the table, for example the axis may be located at or near the distal end of the fixed member. In these cases, the rotatable member may be capable of adopting an orientation which is located in a vertical plane radial to the axis of the table (commonly when it is in its central orientation) but may be capable of rotating horizonally out of the radial plane.

The stabiliser may comprise a rotation device, for example a hinge or a cam/cam follower. The rotation device may be any suitable device which can enable diagonal rotation of the rotatable member, i.e. rotation of the rotatable member or the distal end thereof in a diagonal plane, as described above.

The rotatable member may be rotatable through a horizontal non-zero angle. The non-zero angle may be up to about 60°, particularly in the event that the axis rotation of the rotatable member is at or adjacent the vertical axis of the table. It may be rotatable through a non-horizontal angle of up to about 50, 40 or 30°. It may be rotatable through a non-horizontal angle of up to about 30° in either direction either side of a central position, or up to about 25, 20 or 15°. In some embodiments the rotatable member is rotatable through a horizontal non-zero angle of greater than about 60°, e.g. up to about 120°. This is particularly the case when the axis of rotation of the rotatable member is at some distance from the vertical axis of the table. In this case the rotatable member may be rotatable through an angle of up to 180°, or up to about 90° in either direction either side of a central position. The rotatable member may be rotatable through a horizontal non-zero angle such that, in any accessible orientation of the rotatable member, an angle formed at the vertical table axis by a line from the distal end of the rotatable member to the table axis and a line from the distal end of any one of the fixed legs of the table to the table axis is at least about 60°. This latter requirement promotes stability of the table when the rotatable member is adjusted so that the rotatable member and three legs of the table all are in contact with the ground (or a surface on which the table is located).

When the rotatable member rotates in a diagonal plane, horizontal rotation of the member through a horizontal angle is accompanied by corresponding vertical rotation, leading to vertical movement of a distal end of the rotatable member. The vertical movement may be through a non-zero angle of up to about 4°, depending on the horizontal rotation and on the angle of the diagonal plane in which the member or its distal end rotates. In some embodiments the vertical movement may be through a non-zero angle of greater than about 4°, e.g. up to about 5, 6, 7, 8, 9, 10, 15 or 20°. Larger vertical angles may be useful in cases where the axis of rotation of the rotatable member is at some distance from the vertical axis of the table.

The rotatable member may comprise a foot for contacting the ground. The foot may be disposed at or near the distal end of the member. The foot may have a high friction ground-contacting surface. The foot may be located at or near the distal end of the rotatable member or may be located at some other location on the rotatable member. The foot have limited movement so as to accommodate irregularities in the ground or surface on which the table is located. This also applies to feet on the fixed legs of the table.

In the following discussion, it is assumed for simplicity of description that the distal end of the rotatable member is that portion of the member that contacts the ground when the table has been stabilised, since this is commonly the case. However in some cases some other contacting portion of the rotatable member than the distal end may contact the ground instead. It will be understood that in such cases the operation of the stabiliser will be essentially the same as described below, with the exception that the contacting portion of the rotatable member is substituted for the distal end. For example, the rotatable member may comprise a foot for contacting the ground which may be located elsewhere than at the distal end of the rotatable member.

The rotation device may comprise a diagonal cam, i.e. a diagonal track coupled to, optionally part of, a vertical shaft. In this case the rotatable member may comprise a cam follower, e.g. a projection which can follow the diagonal track so as to cause rotation of the member in a diagonal plane. This is described further in the specification with reference to the Figures. The diagonal track may rotate downwards to the right or may rotate downwards to the left. In the former case, rotation of the rotatable member in an anticlockwise direction when viewed from above results in the distal end of the rotatable member moving downwardly, and in the latter case, rotation of the rotatable member in a clockwise direction when viewed from above results in the distal end of the rotatable member moving downwardly. Thus when three fixed legs are in contact with the ground and the stabiliser is not in contact with the ground, rotating the rotatable member about the hinge axis in the appropriate direction (which may be achieved readily by use of an operator's foot) can result in the distal end of the member dropping sufficiently to contact the ground. When this is achieved, the three fixed legs and the stabiliser all contact the ground, so as to stabilise the table.

The rotation device may comprise a hinge having a non-vertical hinge axis. The “hinge axis” as used here is the axis about which the portions of the hinge rotate relative to each other. The hinge axis may be near vertical. It may be at an angle of greater than about 80° to the horizontal (i.e. less than about 10° to vertical), or greater than about 85° to horizontal, or about 80 to about 89° to horizontal, or about 80 to 88, 80 to 87, 80 to 86, 80 to 85, 81 to 89, 82 to 89, 83 to 89, 84 to 89, 85 to 89, 84 to 88 or 85 to 87° to horizontal, e.g. about 80, 81, 82, 83, 84, 85, 86, 87, 88 or 89° to horizontal. The closer to vertical (i.e. the smaller the angle to the vertical), the smaller the vertical movement of the distal end of the rotatable member will be for a particular horizontal movement.

The hinge axis may be located in a vertical plane which extends radially, or approximately radially, from the table axis. In this case the hinge axis is preferably angled outwardly from its upper end, i.e. the upper end of the hinge is nearer to the table axis than the lower end of the hinge. The consequent angle to the horizontal of the hinge axis is described above. Commonly the rotatable member will extend at an angle to the hinge axis, so that the distal end of the rotatable member is level with or below the level of the lower end of the hinge. This reduces the chance that the hinge contacts the ground and thereby protects the hinge from damage. In this option, the distal end of the rotatable member is at its highest point when the member is in the vertical plane extending radially or approximately radially from the table axis. As the rotatable member is rotated further from that plane, the distal end of the rotable member drops below that highest point. Thus when three fixed legs are in contact with the ground and the stabiliser is not in contact with the ground, simply rotating the rotatable member about the hinge axis (which may be achieved readily by use of an operator's foot) can result in the distal end of the member dropping sufficiently to contact the ground. When this is achieved, the three fixed legs and the stabiliser all contact the ground, so as to stabilise the table.

The hinge axis may be located in a circumferential plane, i.e. in a vertical plane which is tangential to a circle whose centre is the table axis. The hinge axis may be angled from upper left to lower right or may be angled from upper right to lower left, when viewed towards the table axis. In the former case, rotation of the rotatable member about the hinge axis towards the right (i.e. in an anticlockwise direction when viewed from above) results in the distal end of the rotatable member moving upwards, and rotation of the rotatable member about the hinge axis to the left (i.e. in an anticlockwise direction when viewed from above) results in the distal end of the rotatable member moving downwards. In the latter case, the converse applies, i.e. rotation of the rotatable member about the hinge axis towards the right (i.e. in an anticlockwise direction when viewed from above) results in the distal end of the rotatable member moving downwards, and rotation of the rotatable member about the hinge axis to the left (i.e. in an anticlockwise direction when viewed from above) results in the distal end of the rotatable member moving upwards. In either case, when three fixed legs of the table are all in contact with the ground and the rotatable member is not in contact with the ground, rotation of the rotatable member in the appropriate direction (as described above) can contact the distal end of the rotatable member with the ground, thereby stabilising the table.

The table may comprise a return mechanism for returning the rotatable member to a central position. The central position may be one in which the rotatable member is located in a plane which extends radially from the table axis. In the case of a stabiliser having a hinge axis in an approximately radial plane relative to the table axis, the central position may be a position in which the distal end of the rotatable member is at its highest position. In the case of a stabiliser comprising a cam, or a stabiliser having a hinge axis in a circumferential plane, the central position may be one in which the distal end of the rotatable member is approximately mid way between its highest and lowest positions. The return mechanism may comprise for example a spring or other resilient return device.

The rotatable member may be operable by a foot of an operator. Thus in operation a waiter or other operator may rotate the rotatable member into a position in which three fixed legs of the table and the rotatable member all contact the ground (or surface on which the table is located) simultaneously, thereby stabilising the table and inhibiting rocking thereof. Operation by foot is convenient and hygienic. Thus a waiter may be carrying plates, drinks or other matter while operating the present invention. As the invention may be foot operated, there would be no need for the waiter to first deposit the plates etc. elsewhere prior to operating the invention. This provides convenience of operation. Additionally, the stabiliser is located under the table top and is likely to have feet (e.g. of patrons sitting at the table) rested thereon. It is therefore likely to have dirt and/or bacteria on the surface thereof. As the invention may be operated without use of the hands of the operator, this reduces the likelihood of the dirt and/or bacteria being transferred to plates, cups, food etc. handled by the operator. This provides improved hygiene.

The table may comprise a locking mechanism for locking the rotatable member in a fixed position. The locking mechanism may be capable of locking the rotatable member in any desired position or it may be capable of locking the rotatable member in a discrete set of positions. It may be capable of locking the rotatable member in a position such that it is contacting the ground. The locking mechanism may form part of the rotation device or hinge. Thus the hinge may be a lockable hinge. The locking mechanism may form part of the stabiliser. It may be separate from the stabiliser. It may be coupled to or associated with one or more of the legs of the table. It may be coupled to or associated with a support shaft of the table. The locking mechanism may comprise a high friction (e.g. rubberised, textured etc) coating on a foot of the rotatable member, so that when the rotatable member is in a position such that the three fixed legs of the table and the rotatable member are all in contact with the ground the weight of the table provides sufficient friction that the rotatable member does not change position. The locking mechanism may comprise a friction pad which may be applied to the rotatable member when it is in a desired position so as to prevent or inhibit rotation of the rotatable member. It may comprise a pin and socket locking mechanism. It may comprise some other suitable locking mechanism.

In some embodiments of the invention the legs and the stabiliser are be coupled to a support shaft which supports a tabletop. The legs may extend outwardly and optionally slightly downwards from the support shaft. Such arrangements are common in café tables. The rotatable member may also extend outwardly and optionally slightly downwards from the support shaft. In some instances, described above, the stabiliser comprises a fixed member and a rotatable member. In this instance the fixed member may extend outwardly from the support shaft. The rotatable member, when in its central position, may be collinear with the fixed member, so that the fixed member and the rotatable member form a straight member which extends outwardly from the central shaft.

The fixed legs and the rotatatable member (or the rotatable member in combination with the fixed member if a fixed member is present) may extend approximately equal distances from the support shaft, or from the table axis. In some embodiments the rotatable member has variable length. It may be extendable and/or retractable. It may be for example a telescopic member. It may comprise an inner member which fits within an outer member and which can move into said outer member so as to retract the telescopic member and can move out of said outer member so as to extend the telescopic member. The variable length member may comprise an extension lock so as to lock the member at a desired length. The extension lock may comprise a removable pin which can be removably inserted into two or more aligned holes in the variable length member so as to lock the member at the desired length. The use of a variable length member may serve to accommodate a larger degree of unevenness in the ground or other surface on which the table is located while allowing the table to be stabilised as described elsewhere herein.

In other embodiment of the invention the legs and the stabiliser directly coupled to a tabletop so as to support said tabletop. In these embodiments the legs may be substantially vertical members. The stabiliser may also comprise a substantially vertical member. In this case either a substantially horizontal fixed member is attached to the substantially vertical member (the rotatable member being coupled to the substantially horizontal fixed member) or the rotatable member is attached to the substantially vertical member.

The invention also encompasses a table stabiliser comprising a rotatable member, a rotation mechanism for allowing the rotatable member to rotate and an attachment device for attaching the stabliliser to a table portion. Once the stabiliser is attached to the table portion, it forms a table as described above. The rotatable member, attachment device and mode of operation are therefore as described earlier. The attachment device will depend on the nature of the table portion to which the stabiliser is attached. It may for example comprise a clamp, or a screw attachment or some other suitable attachment device.

The invention also provides a method for stabilising a table as described above. This method comprises locating the table on the ground such that three legs of said table contact the ground and the stabiliser is not in contact with the ground. The rotatable member may then be rotated so as to cause downwards vertical motion of the distal end (or of a ground contacting surface) of the rotatable member. Upon sufficient rotation, sufficient vertical motion ensues as to cause the member (i.e. the distal end or ground contacting surface thereof) to come in contact with the ground. The degree of rotation will depend on the angle of the plane in which the rotatable member rotates to the horizontal, and will also depend on the topography of the surface on which the table is located. Commonly the angle of said plane will be such that for most surfaces the horizontal angle of rotation will be less than about 60°. It may be less than about 30° from a central position of the rotatable member. This may ensure that the distal end, or ground contacting surface, of the stabiliser is sufficiently distant from an adjacent fixed leg as to promote stability of the table against tipping.

As discussed above, in preferred embodiments the rotating may be caused by the foot of an operator. It may be caused by a shoe or boot or other item of footwear worn on the foot of the operator. The rotatable member may comprise a foot for contacting the ground. In that case, the foot may be disposed at or near the distal end of the member. The step of rotating may cause the foot to come in contact with the ground. The foot may comprise a ground contacting surface, which may be a high friction (e.g. rubberised) ground contacting surface.

In a preferred embodiment the invention relates to a table with a central vertical post and four or more legs radiating outwards from the bottom of the post as is the accepted and established method. One of these legs functions as a stabiliser and is hinged, preferable near the central post but optionally at some other location along the length of the leg, so that the leg moves in an arc which is predominantly horizontal. The leg is designed in such a way that its movement through this arc also changes the height of the leg in relation to the other fixed legs. As the height changes it may compensate for any unevenness of the surface of the floor or ground. A preferred method is for the movable leg or stabiliser to have a central position which is set at standard height and is equidistant from the other legs either side of it. As the leg is moved in a horizontal arc in one direction the leg also raises. If the leg is moved in a horizontal arc in the other direction then the leg lowers. In this way it is possible to achieve stability no matter which leg of the table is touching the high point of the surface on which the table is located. Movement of the leg may be effected with the foot, so that touching with bare hands is not required. This results in better hygiene and/or more convenient operation.

There is more than one mechanical means for achieving the above result. The leg hinge axis can be at an angle which is not parallel with the vertical axis of the table. This angle may be anywhere between 1 degree and 44 degrees from the vertical but commonly between 2 and 6 degrees. In this manner, when the leg is moved predominantly in the horizontal arc then it also changes height. FIGS. 1 a and 1 b shows a table constructed this way. Thus in FIG. 1 a, table 10 comprises a table top 12 supported at its centre by vertical post 14. Fixed legs 16, 18 and 20 extend outwardly from the lower end of post 14. They are each fitted with a foot (22, 24 and 26 respectively) for contacting the ground. Stabiliser 28, also coupled to the lower end of post 14, comprises hinge 30 and rotatable member 32. Rotatable member 32 is fitted with foot 34 for contacting the ground. Hinge 30 allows rotation of member 32 in a diagonal plane which slopes down towards the back left of table 10 as shown in FIG. 1 a, so that rotation of rotatable member 32 in a clockwise direction (as viewed from above) causes foot 34 to move downwards. The detail view in 1 b shows how the pivot/hinge is angled away from the vertical. FIG. 1 b shows table 10 of FIG. 1 a with an expanded view of hinge 30. Thus hinge 30 comprises mounting block 36 fixed to central post 14. Mounting block 36 is coupled to mounting bracket 38 of member 32 by means of pin 40, which passes through holes (not shown) in block 36 and bracket 38. Mounting block 36 is mounted on post 14 at a slight angle, so that the hole through block 36 is at a small angle (typically about 4°) to the vertical, and consequently pin 40, which is aligned along the axis of hinge 30, is also at this angle. This angle allows vertical movement of foot 34 when member 32 is rotated. Image 1 c shows how the leg is moved in an arc. Due to the angle of pin 40, this arc lies in a plane that is at a small angle to the horizontal, in order to enable vertical movement of foot 34. Typically the range of the arc is no greater than 30 degrees in either direction, for reasons of stability. Image 1 d shows how the leg is raised when moved in one direction, due to the fact that pin 40 (and hence the axis of hinge 30) is angled such that the upper end is towards the back left as shown. Thus FIG. 1 d shows table 10 in a configuration where member 32 is forward of the central position shown in FIGS. 1 a to 1 c, and consequently foot 34 in FIG. 1 d is higher than in FIGS. 1 a to 1 c. Image 1 e shows how the leg lowers when moved in the other direction. FIG. 1 e shows table 10 in a configuration where member 32 is rearward of the central position shown in FIGS. 1 a to 1 c, and consequently, for the reasons described above, foot 34 in FIG. 1 e is lower than in FIGS. 1 a to 1 c. In operation of table 10 an operator would attempt to locate feet 22, 24 and 26 on the ground simultaneously. In some cases, depending in part on the topology of the ground, it may be necessary to rotate member 32 anti-clockwise so as to raise foot 34 in order to achieve this. Once feet 22, 24 and 26 are all in contact with the ground, member 32 may be rotated clockwise until foot 34 contacts the ground. At that stage, all four feet would be in contact with the ground, so that table 10 would be stable and resist rocking.

A second mechanical means of achieving the same result is by a cam system as shown in FIGS. 2 a to 2 f. In this case the moveable leg pivots on a vertical axis. The leg has a cam follower that follows a cam which in this case is mounted on the central post. When the leg is moved in a horizontal arc it also changes height as dictated by the cam and cam follower. Thus in FIG. 2 a, table 50 comprises table top 52 supported by support shaft 54. Legs 56, 58 and 60, having feet 62, 64 and 66 respectively at the distal ends thereof, extend outwardly from the lower end of support shaft 54. Stabiliser 68 comprises rotatable member 70, which extends extends outwardly from the lower end of support shaft 54 and which has foot 72 at the distal end thereof. Member 70 is rotatable by means of diagonal cam 74, which is shown in an expanded view at the bottom of FIG. 2 a. Shaft 54 is fitted with diagonal cam 76 and member 70 is fitted with complementary cam follower 78. Cam follower 78 comprises roller 80, which can roll along diagonal cam 74, and an axle (not shown), coupled to roller 80 and to member 70. Lower support 82 of member 70 can move vertically to allow for vertical movement of member 70 as it rotates about shaft 54.

FIG. 2 b shows view of table 50 of FIG. 2 a showing the underside of the rotation mechanism. In particular, lower support 82 is shown mounted on guide shaft 84 which extends downwards from the bottom of support shaft 54. Thus support 82 can slide up and down guide shaft 84 so as to allow vertical movement of rotatable member 70. End 86 of guide shaft 84 is wider than the rest of guide shaft 84 to prevent support 82 from coming off shaft 84. This also limits the range of rotation of rotatable member 70, so as to prevent it rotating to a position in which it is sufficiently close to fixed leg 56 that table 50 is unstable. Commonly, rotatable member 70 can not rotate to less than 60° from leg 56.

FIG. 2 c shows a view of table 50 along member 70. This clearly shows how horizontal rotation of member 70 causes roller 80 to move along cam 74 so as to member 70 to move in a vertical direction also.

FIG. 2 d illustrates the operation of table 50. Thus movement of member 70 in an anticlockwise direction (as viewed from above) causes roller 80 to move to the right along cam 74 thereby causing attendant upwards movement of member 70. FIG. 2 e shows how movement of member 70 in a clockwise direction (as viewed from above) causes roller 80 to move to the left along cam 74 thereby causing attendant downwards movement of member 70. Thus in use, feet 62, 64 and 66 are located on the ground and member 70 is moved in a clockwise direction (when viewed from above), it moves downwards until it reaches a position in which foot 72 meets the ground. In this position each of feet 62, 64, 66 and 72 are in contact with the ground, and table 50 is stable against rocking.

Yet another mechanical means to achieve the above result is shown in FIGS. 3 a and 3 b. In FIGS. 3 a and 3 b the hinge pivot axis is not parallel to the vertical table axis. In this case the leg will move downwards when rotated on the arc in one direction and it will also move downwards when rotated on the arc in the other direction. Thus in FIG. 3 a, table 100 comprises table top 102 supported by support shaft 104. Legs 106, 108 and 110, having feet 112, 114 and 116 respectively at the distal ends thereof, extend outwardly from the lower end of support shaft 104. Stabiliser 118 comprises rotatable member 120, which extends outwardly from the lower end of support shaft 104 and which has foot 122 at the distal end thereof. Member 120 is rotatable by means of hinge mechanism 126, which is shown in an expanded view at the bottom of FIG. 3 a. The hinge axis of hinge mechanism 126 is located in a vertical plane which extends approximately radially from support shaft 104. It is angled outwardly from its upper end as shown in FIG. 3 b. In this example it is angled at about 8° to the vertical. Thus mounting block 128 is fixed to support shaft 104 and has a hole passing through it at the desired angle of the hinge axis. Member 120 comprises mounting bracket 130 at its proximal end, bracket 130 being configured to fit around block 128. Axial pin 132 passes through bracket 130 and block 128 along the hinge axis so as to attach member 120 to shaft 104 in a manner that enables rotation of member 120 about the hinge axis. Member 120 extends from bracket 130 at an angle, so that it extends either horizontally or slightly below horizontally. In the example shown in FIG. 3 a, it extends horizontally, and comprises foot 122 at its distal end for contacting the ground. FIG. 3 b shows a side view of table 3 a, which clarifies the angles between support shaft 104, block 128, bracket 130, pin 132 and member 120. In the configuration where member 104 extends outwardly from support shaft 104 in the plane defined by shaft 104 and the hinge axis of hinge mechanism 126, foot 122 is at its highest position. As rotatable member 104 is rotated further from that plane, the distal end of the rotable member (and consequently foot 122) drops below that highest point. Thus in operation, feet 112, 114 and 116 are all located on the ground. Rotatable member 104 is then rotated about the hinge axis until the foot 122 moves downwards sufficient to contact the ground. When this is achieved, all 4 feet 112, 114, 116 and 122 contact the ground, so as to stabilise the table.

In tables 10 and 100 described above, a mounting block (36 or 128) is attached to the support shaft (14 or 104) and a mounting bracket is part of the rotatable member (28 or 118). Clearly an equally suitable arrangement may be achieved with a mounting bracket being attached to the support shaft and a mounting block forming part of the rotatable member. In such cases, the operation of the table would be the same as described above.

FIG. 4 illustrates a hinge pivot point that is closer to the outer end of the leg rather than being adjacent to the central post of the table. Otherwise, the configuration and operation of table 150 of FIG. 4 is the same as for table 10 of FIG. 1. Clearly, the hinge mechanisms illustrated in FIGS. 2 a and 3 a could be substituted in the table of FIG. 4 also. Thus in FIG. 4, table 150 comprises a table top 152 supported at its centre by vertical post 154. Fixed legs 156, 158 and 160 extend outwardly from the lower end of post 154. They are each fitted with a foot (162, 164 and 166 respectively) for contacting the ground. Fixed member 168 also extends outward from support shaft 154. Stabiliser 170, coupled to the distal end of fixed member 168, comprises hinge 172 and rotatable member 174. Rotatable member 174 is fitted with foot 176 for contacting the ground. Hinge 172 allows rotation of member 174 in a diagonal plane which slopes down towards the back left of table 150 as shown in FIG. 4, so that rotation of rotatable member 174 in a clockwise direction (as viewed from above) causes foot 176 of member 174 to move downwards. The axis of hinge 172 is angled away from the vertical. Hinge 172 comprises mounting block 178 which forms the distal end of fixed member 168. Mounting block 178 is coupled to mounting bracket 180 of member 174 by means of pin 182, which passes through holes (not shown) in block 178 and bracket 180. Mounting block 178 is set at a slight angle, so that the hole through block 178 is at a small angle (typically about 4°) to the vertical, and consequently pin 182, which is aligned along the axis of hinge 172, is also at this angle. This angle allows vertical movement of foot 176 when member 174 is rotated.

FIG. 5 a shows a return mechanism which may be used for returning the rotatable member to its central position. Table 200 of FIG. 5 a is an adaptation of table 10 of FIG. 1, and its operation will be similar to that described above for table 10. Thus in FIG. 5, table 200 comprises a table top 202 supported at its centre by vertical post 204. Fixed legs 206, 208 and 210 extend outwardly from the lower end of post 204. They are each fitted with a foot (212, 214 and 216 respectively) for contacting the ground. Stabiliser 218, also coupled to the lower end of post 204, comprises hinge 220 and rotatable member 222. Rotatable member 222 is fitted with foot 224 for contacting the ground. Hinge 220 allows rotation of member 222 in a diagonal plane which slopes down towards the back left of table 200 as shown in FIG. 5 a, so that rotation of rotatable member 222 in a clockwise direction (as viewed from above) causes foot 224 to move downwards. Hinge 220 is shown in detail in the expanded diagram at the bottom of FIG. 5 a. It comprises mounting block 226 fixed to central post 204. Mounting block 226 is coupled to mounting bracket 228 of member 222 by means of pin 230, which passes through holes (not shown) in block 226 and bracket 228. Mounting block 226 is mounted on post 204 at a slight angle, so that the hole through block 226 is at a small angle to the vertical, and consequently pin 230, which is aligned along the axis of hinge 220, is also at this angle. FIG. 5 a shows a cut-away view of member 226 so that the return mechanism is visible. Hinge 220 also comprises spring 232, which is fixed at one end to rotatable member 222, by means of anchor pin 234, and at the other end to centring plate 236. Spring 232 urges centring plate 236 against the face of mounting block 226. FIG. 5 b shows a horizontal section through hinge 220, showing how centring plate 236 urges against mounting block 226. It also illustrates how spring 232 is retained in place by shaft 238 of centring plate 236, and shows hole 240 (not visible in FIG. 5 a) in which pin 230 is located so as to couple mounting block 226 to bracket 228. In its central position, shown in FIGS. 5 a and 5 b, in which rotatable member 222 is orthogonal to both fixed members 206 and 210, centring plate 236 sits flush against face 242 of mounting block 226. However when rotation of member 222 in a horizontal direction moves it away from the central position (so as to either raise or lower foot 224 in order to stabilise table 200) centring plate 236 no longer sits flush against face 242 and instead contacts only either edge 244 (if member 222 rotates clockwise as viewed from above) or edge 246 (if member 222 rotates anti-clockwise as viewed from above). In either case, this gives rise to a return force which tends to return member 222 to the central position. Unless a counteracting force is present (e.g. due to an operator or to friction of foot 224 with the ground or other surface), this return force will tend to return member 222 to that central position. In operation, once rotatable member 222 has been rotated so that all 4 feet 212, 214, 216 and 218 are located on the ground, friction of foot 224 on the ground, enhanced by the weight of table 200, prevents return of member 222 to the central position. However once the table is moved (e.g. lifted or tilted) so that foot 224 is no longer on the ground, spring 222 returns member 222 to the central position.

In summary, the invention provides a table leg that is hinged to move in a substantially horizontal arc which at the same time changes height, so as to compensate for uneven floor surfaces. 

1. A table comprising at least three legs and a stabiliser, wherein said stabiliser comprises a rotatable member extending outwardly from a vertical axis of said table.
 2. The table of claim 1 wherein the stabiliser comprises a rotation device which enables diagonal rotation of the rotatable member.
 3. The table of claim 1 wherein the rotatable member is rotatable through a horizontal non-zero angle of up to about 60°.
 4. The table of claim 1 wherein rotation of the member through a horizontal angle is accompanied by vertical movement of a distal end of said member through a non-zero angle of up to about 4°.
 5. The table of claim 1 wherein the rotatable member comprises a foot for contacting the ground, said foot being disposed at or near a distal end of the member.
 6. The table of claim 2 wherein the rotation device comprises a diagonal cam.
 7. The table of claim 2 wherein the rotation device comprises a hinge having a non-vertical hinge axis.
 8. The table of claim 7 wherein said hinge axis is located in a vertical plane which extends radially from the table axis, said hinge axis being angled outwardly from its upper end.
 9. The table of claim 7 wherein said hinge axis is located in a circumferential plane.
 10. The table of claim 1 comprising a return mechanism for returning the rotatable member to a central position.
 11. The table of claim 10 wherein the central position is one in which the rotatable member is located in a plane which extends radially from the table axis.
 12. The table of claim 1 wherein the rotatable member is operable by a foot of an operator.
 13. The table of claim 1 comprising a locking mechanism for releasably locking the rotatable member in a fixed position.
 14. The table of claim 1 wherein the legs and the stabiliser are coupled to a support shaft which supports a tabletop.
 15. The table of claim 1 wherein the legs and the stabiliser are directly coupled to a tabletop so as to support said tabletop.
 16. A method for stabilising a table having at least three legs and a stabiliser, the stabiliser including a rotatable member extending outwardly from a vertical axis of the table, said method comprising: locating the table on the ground such that three legs of said table contact the ground and the stabiliser is not in contact with the ground; and rotating the rotatable member so as to cause said member to come in contact with the ground.
 17. The method of claim 16 wherein said rotating is caused by a foot of an operator.
 18. The method of claim 16 wherein the rotating is through a horizontal angle of less than about 60°.
 19. The method of claim 16 wherein the rotatable member comprises a foot for contacting the ground, said foot being disposed at or near a distal end of the member, and the step of rotating causes the foot to come in contact with the ground. 